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queue.js
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queue.js
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'use strict';
var Promise = require('bluebird');
module.exports = class Queue {
constructor() {
this.reset();
}
run() {
this.disabled = false;
this.checkQueue();
}
reset() {
this.queue = [];
this.disabled = true;
this.activeTask = null;
}
push(handler) {
var defer = Promise.pending();
this.queue.push(defer);
this.checkQueue();
var promise = defer.promise.then(handler);
this.finishActiveTaskWith(promise);
return promise;
}
checkQueue() {
if (!this.disabled && !this.activeTask && this.queue.length) {
this.activeTask = this.queue.shift();
this.activeTask.resolve();
}
}
finishActiveTaskWith(promise) {
promise.bind(this).finally(() => {
this.activeTask = null;
this.checkQueue();
});
}
};